2003 GMC Yukon Owner's Manual - Page 205

Oil Pressure Gage A reading in the low pressure zone may be caused by a dangerously low oil level or some other problem causing low oil pressure. Check your oil as soon as possible. See Oil Pressure Low under DIC Warnings and Messages on page 3-64 and Engine Oil on page 5-16. {CAUTION: Do not keep driving if the oil pressure is low. If you do, your engine can become so hot that it catches fire. You or others could be burned. Check your oil as soon as possible and have your vehicle serviced. United States Canada The oil pressure gage shows the engine oil pressure in psi (pounds per square inch) when the engine is running. Canadian vehicles indicate pressure in kPa (kilopascals). Oil pressure may vary with engine speed, outside temperature and oil viscosity, but readings above the low pressure zone indicate the normal operating range. Notice: Damage to your engine from neglected oil problems can be costly and is not covered by your warranty. 3-51